Marks and Spencer clothing sales hit by warm September

British retailer Marks and Spencer posted mixed half-year profits on Wednesday as warmer-than-expected weather dented demand for autumn-style clothing, while its food unit reported strong sales.

Net profit dropped 8.5 percent to £228.3 million ($364 million, 291 million euros) in the six months to late September compared with the equivalent period in 2013, M&S said in an earnings statement.

Underlying pre-tax profit rose 2.3 percent to £268 million in the latest reporting period. The better than expected result sent M&S shares surging to the top of London's FTSE 100. "Within clothing, womenswear performance continues to improve with growth in full price sales and increasingly positive feedback from our customers," the statement said.

"However, the recent market conditions remain challenging, with unseasonal weather resulting in high levels of promotional activity across the market... We expect our food business to continue to outperform the market with a higher number of new Simply Food stores planned over the next three years, up to 200 from 150 previously guided," it added.

The group's share price surged 6.33 percent to 430.3 pence on the benchmark FTSE 100, which was up 0.50 percent at 6,486.22 points in early deals.

"The profit beat (forecasts) and improvement to gross margins have taken investors by surprise, with the share price strongly ahead," said Richard Hunter, head of equities at Hargreaves Lansdown Stockbrokers.